Abstract Optical metasurfaces, planar subwavelength nanoantenna arrays with the singular ability to sculpt wavefront in almost arbitrary manners, are poised to become a powerful tool enabling compact and high-performance optics with novel functionalities. A particularly intriguing research direction within this field is active metasurfaces, whose optical response can be dynamically tuned postfabrication, thus allowing a plurality of applications unattainable with traditional bulk optics. Designing reconfigurable optics based on active metasurfaces is, however, presented with a unique challenge, since the optical quality of the devices must be optimized at multiple optical states. In this article, we provide a critical review on the active meta-optics design principles and algorithms that are applied across structural hierarchies ranging from single meta-atoms to full meta-optical devices. The discussed approaches are illustrated by specific examples of reconfigurable metasurfaces based on optical phase-change materials.

中文翻译：

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质量设计：基于有源超表面的可重构平面光学器件

摘要 光学超表面，平面亚波长纳米天线阵列，具有以几乎任意方式雕刻波前的奇异能力，有望成为一种强大的工具，可实现具有新颖功能的紧凑型高性能光学器件。该领域一个特别有趣的研究方向是有源超表面，其光学响应可以在制造后动态调整，从而实现传统体光学无法实现的多种应用。然而，设计基于有源超表面的可重构光学器件面临着独特的挑战，因为必须在多个光学状态下优化器件的光学质量。在本文中，我们对应用于从单个元原子到完整元光学器件的结构层次结构的有源元光学设计原则和算法进行了批判性审查。所讨论的方法通过基于光学相变材料的可重构超表面的具体示例进行了说明。